DFU OTA suddenly fails on "non secure" bootloaders but works on "secure" bootloaders.

[Lennart Andersson]

Suddenly DFU OTA fails most of the time while trying to update units with code & "not secure" bootloader that has been working for years. The FW upload stops at 2% to 8% but if i restart my phone sometimes it reaches 15% and on happy days I can update the unit after rebooting the phone.

With the same DFU app DFU update works well with another unit with "secure" bootloader.

I am NOT trying to update a unit with "not secure" bootloader with code made for units with "secure bootloader" and vice versa.

What can suddenly be the problem?

Phone: Samsung Galaxy S21 Ultra 5G

Android version: 14

DFU app version: 2.9.0 (build 24123065)

[Vidar Berg]

Hello,

Do you know which SDK the "non-secure" bootloader was based on? It would also be interesting to know if you can reproduce this issue with other phones than the Galaxy s21 if possible. 

You can also view the debug logs in the app by swiping right after the DFU has failed. This may provide us some additional clues.

Best regards,

Vidar

[Lennart Andersson]

Hi Vidar!

I think the bootloader is based on SDK11

I don't get any debug logs if I swipe right after upload fail, Nothing happens.

/Lennart.,

[Lennart Andersson]

There was a rumor that DFU upload on legacy bootloaders works on Iphone and that rumor has now been confirmed as to be true.

- The android app can't DFU OTA  but the Iphone app can. PLease fix it urgently.

[Vidar Berg]

Hi,

Thanks for confirming the SDK version. 

Lennart Andersson said:

I don't get any debug logs if I swipe right after upload fail, Nothing happens.

Are you using the nRF Connect app on Android? 

[Lennart Andersson]

Yes. Samsung Galaxy S21, Android Version 14. But it seems that all android devices share the same problem.

AS I just wrote it has been confirmed that the Iphone app works.

[Vidar Berg]

Thanks for confirming. I'm not sure why you are unable to retrieve the debug logs from the nRF connect app. Anyway, please install the nRF DFU app and and in the app settings, set the PRN (packet receipt notification) to 1. Then install the nRF Logger app and try the DFU again. The nRF DFU app will generate logs in the nRF Logger app.